The present disclosure relates generally to metallic part processing, and, more particularly, to a laser drilling process of metallic parts.
Laser drilling of cylindrical holes generally occurs through melting and vaporization of the work piece material through absorption of energy from a focused laser beam. As a side effect, laser drilling may cause residual stresses and distortion of drilled parts. Both the residual stresses and the distortion are driven by local thermal gradients and their associated gradients in substrate thermal expansion and transient metallic properties. Distortion due to laser drilling is often imperceptible but can be significant in certain structures, in which case a warp will be formed that may cause failure of the structure, failure of associated coatings, or result in a final part or structure that does not satisfy dimensional requirements.
Accordingly, what is desired is a laser drilling method that mitigates distortion without significantly impacting production feasibility and effectiveness.